Heat-assisted magnetic recording (HAMR) is a technology that magnetically records data on recording media using thermal assistance. HAMR can utilize high-stability magnetic compounds that can store single bits in a small area. In general, a HAMR media stack includes a number of layers such as a bottom layer substrate, an adhesion layer on the substrate, an intermediate layer on the adhesion layer, a magnetic recording layer on the intermediate layer, a carbon overcoat layer, and a lubricant layer on the carbon overcoat layer.
In HAMR media manufacturing, a substrate is heated to a suitable temperature before depositing one or more magnetic recording layers. Then the substrate is cooled down before one or more carbon overcoat layers (e.g., a sputtered carbon layer or a diamond-like carbon (DLC) layer) are deposited on the substrate. The temperature for depositing the carbon layers is substantially lower than the deposition temperature of the magnetic recording layers.